How can data be merged in Access database?

There are several ways to merge data in an Access database:

1. By using a query, you can create a new query, link the tables that need to be merged, select the desired fields, and save the result as a new table.
2. With SQL statements, you can write a query using the UNION or UNION ALL keyword to combine the data from two tables into one result set, and then save the result set as a new table.
3. By using the import/export feature, you can export a table from one database into an Excel or CSV file, and then import the file into a table in another database, thereby merging the data.
4. You can use VB or VBA programming to write a VBA program that connects two databases using ADO objects, then copies data from one table to another table to achieve data merging operations.

The above are several common methods for merging Access database data, the specific choice of method depends on the specific requirements and operational scenario.